(a) Technical Field
The present application relates to a display device. More particularly, the present application relates to a display device including a white pixel.
(b) Description of the Related Art
In general, display devices, such as liquid crystal displays (LCDs) and organic light emitting diode displays, include a display substrate having a plurality of pixels including switching elements and a plurality of signal lines, a data driver applying, as a data signal, a gray voltage corresponding to an input image signal among a plurality of gray voltages to data lines, and the like.
The display device includes a self-emissive display device having a light-emitting device emitting light and a non-emissive display device including a backlight.
As a representative example of the non-emissive display device, the liquid crystal display is one of the display devices that are widely used. The liquid crystal display includes a display panel including a plurality of pixels, and a backlight unit supplying the light to the display panel. The display panel includes a liquid crystal layer having dielectric anisotropy, and field generating electrodes such as a pixel electrode and a common electrode generating an electric field to the liquid crystal layer. The pixel electrode may be arranged in a matrix shape and may be connected to the switching element such as a thin film transistor (TFT) to sequentially receive a data voltage row by row. The common electrode is applied with a common voltage Vcom. The pixel electrode and the common electrode are applied with the voltages to generate the electric field to the liquid crystal layer, and an intensity of the electric field is controlled to control the transmittance of the light passing through the liquid crystal layer, thereby obtaining the desired image.
Two field generating electrodes such as the pixel electrode and the common electrode may be positioned at one display panel or may be respectively positioned at two display panels. When the display device includes two display panels, the pixel electrodes applied with a data voltage among the field generating electrodes and a plurality of thin film transistors may be arranged in one display panel of two facing display panels and a color filter representing primary colors such as red, green, and blue and a light blocking member preventing light leakage between the pixel may be formed in the other display panel. Alternatively, the light blocking member may be formed at the same display panel as the pixel electrode and the thin film transistor, in this case, the color filter may also be formed at the same display panel as the pixel electrode.
The non-emissive display device includes a red pixel, a green pixel, and a blue pixel respectively displaying images of three primary colors such as red, green, and blue. The red pixel, the green pixel, and the blue pixel display each primary color to realize various colors. However, the red pixel, the green pixel, and the blue pixel include a colored filter such that a light amount emitted from the backlight is reduced while passing through the color filter, and resultantly the luminance of the image is deteriorated. To solve this problem, a white pixel that does not include the colored filter is further included as well as the color pixels representing the primary colors such as three primary colors to pass more of the light of the backlight than the color pixel. The white pixel does not include the color filter such that the luminance of the image may be increased.
The above information disclosed in this Background section is only for enhancement of understanding of the background and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.